Hills Change What A Walk Does To You

Two walks of the same distance can differ enormously in effort, and gradient is usually the reason. The mechanics of walking uphill and downhill are different enough to be treated as separate activities.

Going up is work against gravity

On the flat, walking mostly moves the body forwards and the vertical work is small. On a slope, every step lifts the whole body a measurable distance upwards.

That lifting is expensive. The demand on the heart and lungs rises steeply with gradient, which is why a modest hill produces breathlessness that a much faster flat walk does not.

The useful consequence is that intensity can be raised without raising speed. Someone who cannot comfortably walk fast can still reach a substantial effort by walking slowly upwards.

The muscles doing the work are different

Uphill walking loads the muscles that extend the hip and knee, and it loads the calves through a larger range. These are the same muscles used for stairs and for standing up.

Because the load is applied repeatedly at moderate force, a hilly walk has some of the character of strength work. It is not a substitute for resistance training, but it is not nothing either.

This is part of why hill walking transfers noticeably to daily life. Stairs and slopes stop registering as obstacles when they have been practised regularly.

Coming down is the harder part for joints

Descending requires muscles to lengthen while resisting, which is how the body absorbs each landing. This kind of contraction produces more muscle soreness than the uphill equivalent.

It also places higher forces through the knees. Many people find a long descent more uncomfortable than the climb, and that experience is consistent with the mechanics.

Shortening the stride, slowing down and using a zigzag line where the path allows all reduce the peak forces. Poles shift some of the load to the arms.

Why hilly routes feel disproportionately tiring

Effort on a hill is uneven. Instead of a steady moderate demand, the walk alternates between hard climbing and the loaded braking of descent, with little of the easy cruising a flat route provides.

Perceived effort tracks the peaks rather than the average. A route with several short climbs can feel harder than a longer flat one that costs more in total.

Route planning therefore benefits from thinking in terms of ascent rather than distance. Two miles with a long climb is a different afternoon from four flat ones.

Building up sensibly

Gradient is a load like any other, and increases in it are best made gradually. Adding a substantial climb to a walking habit is a step up in demand, not merely a change of scenery.

Soreness for a day or two after an unaccustomed descent is common and settles. Pain in a joint that persists, or that appears during the walk rather than after it, is a reason to consult a physiotherapist or doctor.

For most people the practical route in is simply to include one hill in an existing walk. The demand rises immediately and the distance does not have to change at all.